dumb question help

het there,
I am developing a class so you can take your own png and put the skin on an npc.
But after a little research I did found that minecraft skins have a deformed value. so I need to find how to reform it so I now what I need to input and then I need to deform every png file or link
So does somebody knows how I can find this or is it just an id from minecraft?

 

Erm.. The skin needs to be a skin of a actual player.

 

ChipDev
that does already exist, but i am trying to do some NMS but when i output the skin property of a mojang account it looks like 200 random numbers and letters. is it an uuid for a skin or a deformed link to an png file
Edit: I did find something interesting in the source code of minecraft. a mojang account property is a json element so maybe I can do something with this information

 

In the source code of MC?
u hax?
(Or source code of CraftBukkit?)

 

ChipDev
In craftbukkit in the package net.minecraft.util.com.mojang.authlib